circularresendbuffer.h~

实现了SS7中MTP2层的基本功能

// File Name: CircularResendBuffer.h
///////////////////////////////////////////////////

#ifndef _EASYTELECOM_CIRCULAR_RESEND_BUFFER_H_XING_20080903_
#define _EASYTELECOM_CIRCULAR_RESEND_BUFFER_H_XING_20080903_

#include <pthread.h>
#include <string.h>

class CircularResendBuffer
{
public:
    CircularResendBuffer(int _size);
    ~CircularResendBuffer(void);

public:
    int write(unsigned char * _buffer, int _count);
    int read(unsigned char * _buffer, int _count);

    unsigned char * getSentMsgPtr(int & _msgLen);
    void updateReadPos(int _newReadPos); // will be called after sending
    void updateConfirmedPos(int _newConfirmedPos); // unpon receipt of BSN

    int getStoredBytesNumber(void);
    int getFreeBytesNumber(void);
    int getBytesForSend(void);
    unsigned char * getSentMsgPtr(void);

    int reSize(int _newCount);
    int clear(void);

private:
    unsigned char * buffer;
    int    bufferSize;

    int    write_pos;
    int    read_pos;
    int    confirmed_pos;

    pthread_mutex_t mutex_buffer;
};

#endif // _EASYTELECOM_CIRCULAR_RESEND_BUFFER_H_XING_20080903_